1) Every 30 minutes, your soldiers all produce a small amount of gold. You can increase the amount of gold by getting more soldiers. To get more soldiers, you can get more officers, or click links on a recruiter. (Check recruiter list in the barracks, and recruiter discussion in the Great Hall for more information.)

2) Attack for gold. Spy on different players, or have a friend with a higher spy look for you. There are some large players with low defense out there, so look hard before attacking. ;)